SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Site Background Information: Chapin Brothers Investments, Inc. Page 17 of 19 HYDROCARBON-IMPACTED SOIL Forty-two soil samples were analyzed for TPH-g, BTEX, and MTBE; selected samples were analyzed for fuel additives: • TPH-g was detected in twelve of the soil samples analyzed at concentrations as great as 550 milligram per kilogram(mg/kg), in soil sample CB 10-20 (17 feet bsg vertical depth). • TPH-g was not detected in soil samples collected above a vertical depth of 17 feet bsg,and except for sample C137-36 (31 feet bsg vertical depth) near the northeastern corner of the building,TPH-g was not detected in soil samples collected below a vertical depth of 24 feet bsg. • The BTEX compound benzene was detected in twelve of the soil samples analyzed, at a maximum concentration of 11 mg/kg in sample C137-24 (20 feet bsg vertical depth); the benzene concentrations ranged from 0.01 mg/kg to Il mg/kg. Various other BTEX compounds were detected in ten of soil samples analyzed. • The greatest concentrations of BTEX compounds were detected generally in soil samples collected at a vertical depth of 20 feet bsg.The maximum concentration of the other BTEX compounds was detected in sample C137-24 (20') at 110 mg/kg of xylene. • MTBE and other fuel additives were not detected in the analyzed soil samples analyzed. VOLUME MASS CALCULATION A volume-mass calculation of the remaining petroleum hydrocarbon-impacted soil under the building yields an approximate volume of 18,000 ft'or 660 cubic yards. Volume-mass calculations indicate that an estimated 60 gallons of adsorbed TPH-g remain in soil in the area delineated in Figure 2; an averaged concentration of 125 mg/kg TPH-g was used to calculate the total mass of remaining hydrocarbons in soil beneath the building. DISCUSSION/CONCLUSIONS Based on the results of this investigation,supplemented by quarterly ground water monitoring data, AGE concludes: • Ground water was encountered at 17 feet bsg;hydrocarbons odor was detected in saturated sand encountered at the top of the ground water table. • The highest concentrations of TPH-g were detected in soil samples collected between the vertical depths of 17 feet and 20 feet bsg.The maximum hydrocarbon concentrations in soil were detected beneath that portion of the building nearest the former 8,000-gallon USTs located at the eastern edge of the site. Advanced GeoEnvironmental,Inc.